I have three implemented sorting algorithm:
How do I select the averagely fastest sorting algorithm based on the characteristics of the given sequence and return the sorted one. asked 20 Jan '15, 16:35 codebazz 
Considering the average case time complexities of the mentioned algorithms, bubble sort is the worst, Now, while both quicksort and merge sort have the same time complexity, their performance may be different depending on the data. Doing a a merge sort on different data of the same size would require exactly the same number of operations every time. But the number of operations can vary in quicksort. If the data is already sorted, the traditional quicksort would require So, in average case, both quicksort and merge sort have the same time complexity, but in worst case, quicksort and bubble sort can have the same complexity.
For a quick look on complexities of algorithms, you can see this. answered 21 Jan '15, 05:20 0605002 but vaiya, I think you have missed another thing that is if the array is reversely sorted Quick sort may be not perform best and obviously bubble will be the worst for reversely sorted array. Then I think I should select the merge sort for reversely sorted large array. @Sufian Latif vaiya.
(21 Jan '15, 05:52)
codebazz

You can choose the fastest one by knowing their time complexity (How many time it need to sort n numbers in worst case).The lowest time complexity in worst case is the fastest one. The fastest algorithm among 3 is Merge sort (Time complexity: n*log(n)). Here you can find all the information about sorting algorithmsLink. answered 20 Jan '15, 17:15 Kaiser Ahmed 